Polarity reversing switch



S. F. BRIGGS.

POLARiTY REVERSING SWITCH.

APPLICATION FILED FEB. 9. 19:8.

Patented Nov. 25, 1919.

2 SHEETSSHEET 1.

WITNESSES.

S. F. BRIGGS.

POLARITY REVERSING SWITCH.

APPLICATION FILED FEB. 9. 1918.

1,322,870. Patented Nov. 25, 1919.

2 SHEETSSHEET 2.

WITNESSES, VENTOR g2 ATTORNEY.

*ao gas engme for startingthe gas engine in UNITED STATES PATENT o IoE.

STEPHEN F. BRIGGS, F. MILWAUKEE, WISCONSIN, ASSIGNOB TO; BRIGGS daSTRATTON COMPANY, OF MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN.

.Milwaukee, Milwaukee county,

1 ing had to the accompanyin Specification of Letters Patent.

roLAmrY-nnvnnsme swrrcn.

Original application filed February 27, 1915, Seria1 No. 10,883. Divided and this application filed February 1918. Serial No. 216,408.

To all whom it may concern:

Be it known that I, STEPHEN F. BRIGGS, a citizen of the United States, and resident of Wisconsin, have invented newand'useful Improvements in Polarity-Reversing Switches, of .which the following is a description, reference bewhich are a part of this speci cation.

This invention has for its object to provide a switch for controlling an electrical circuit, such as the ignition circuit of a gas engine, and so constructed that the direction of flow of current will be changed by the successive operations of the switch so that the tendency of pitting the contact points at which the circuit may be broken temporarily, as at the make and break of ..'I it tric machine used as a generator for 'charging a storagebattery of an automobile when an induction coil or other contact maker,

will be neutralized by the current flowing in one direction and then in the other direction with the successive operations of the switch.

Another object of the invention is to incorporate such a pole reversing switch as a part of aswitch for controlling other circuits, such as the circuit of a dynamo elecdriven from the gas engine and used as a motor for turning the crank shaft of the yet durable andv efficient constructionwhich will be inexpensive to manufacture.

The present application constitutes a division of'a pli'cation Serial N 0. 10,883, filed February 2 1915, for, pole reversing switch.

With the above and other objects in'view the invention consists in the pole reversing switch as herein claimed and all equivalents.

Referring to the accompanying drawings in which like characters of reference indicate the same parts in the different views:

Figure 1 is a front iew of a switch con: structed in accordance with this invention;

Fig. 2 is a rear View thereof;

Fig. 3 is a "transverse sectional view thereof; I v

Fig. 4 a rear s'ectional view on the plane of line 4-4 6f Fig.3 with the switch in its off position;

drawings,

showing the contact disk in its bearing on the casing and on theinsulated contact respectively Fig. 9 is a similar view with the contact disk removed and showing the lock for locking the switch in its off position;

Fig. 10 is a sectional view through the cylindrical switch member and showing the plunger switch contact members carried thereby;

Fig. 11 is a detail view showing the manner. of engagement of the pole changing switch contacts with two-adjacent contact buttons; and, I p

Fig. 12 is a diagram showing the wiring connections fora switch or this character.

'In these drawings 10 indicates a, front plate which is designed to be let into the dash of an automobile and forms a cylindrical housing for the switch base 11 of insulating material which telescopes there- -with from the rear and is held in place by means of countersunk screws 12 threading into bosses 13 of the front plate. The switch of this invention is of the type of switch covered by my co-pending application for switches, which resulted in Letters Patent No. 1232650, dated July 10, 1917. The base 11 is hollow and a. cylindrical switch member 14 which in this case is preferably of metal, instead of insulating material .as before, is held by screws 15 surrounded by in; sulating bushings to the back of a turning plate 16 and is contained Within the recess of the base and is rotatable through an arc of approximately 90, said turning plate 16 having a suitable guide seat in. the front plate 10 to permit of such movement, and carrying a projecting handle 17 by means of which the turning may be accomplished. A stop lug on the back of the turninglplate 16 engages shoulders of the front p te 10 to limit the turning movements of the Patented Nov. 25, 1919.

with the switch in switch. A look 19 base 11, said studs originally projecting part way into the recess or cavity of the base, but

having openings therein into which later being turned out or reamed out to conform with the cylindrical inner wall of the base to form stationary contacts diametrically opposite each other. Nuts 24 and washers 25 on the threaded projecting ends of the studs form bindingposts for connection with 'the armature of the motor generaioi and the storage battery respectively. Another stud 26. similar to the studs 22 and 2;), though dcsu'-.\bly somewhat smaller, is positioned between the other studs and the nuts and washers thereon form a binding post for ccnncction with the shunt field winding of the motor generator.

An opening 28 passes diametrically through the switch member 14 and has a pair of spring resse d switch contact members 29 fittin t erein which are in the form. of plugs sli ably mounted in the o ening and are electrically connected by a flexible conductor 30, The contact members 29 are firmly secured to the ends of the flexible conductor 30, by

drilled longitudinally the ends of the conductor are inserted and by havin transverse openings drilled nearly to the l ongitudinal openings, leaving a thin partition of metal between the openings which is then struck with a punch at the edge thereof near the outer end of the contact member so as to drive the artition inwardly as a tongue to bite into t e yielding flexible conductor, as covered in my co-pending application referred to. This means of connecting the con-' tact members on the ends of the flexible conductor forms a strong mechanical connection firmly connecting the parts and assuring an electrical connection of low resistance between them. The flexible conductor is surrounded by a coil spring 32 bearing at its ends against the contact members 29 and forcing them apart in close contact with the inner walls of the base and particularly with the stationary contacts 22 and 23 to form an electrical connection between them in the starting or on position of the switch. In order that the contact members 29 may not fit too freely within the opening 28 the coil spring 32 is preferably bent or bowed at its middle portion so as to bear against the walls of the opening.

Instead of a spring-contact or brush coning post or stud 81 surrounded commonly known as a pigtails but are insulated thereby nection from the contact members 29 and stud 26 as before, provision is made for groundin the stud 26 on the casing when the switci is turned to its closed or on position. For this purpose a metal disk is interposed between the switch member 14 and the lock 19 with a sheet of insulating material 76 between it and the switch member 14, said metal disk 7 5 having one or more spring tongues 77 cut therefrom and bent outwardly to bear with spring pressure against the inwardly projecting flange 78 around the central opening of the front plate 10; and a projection from the edge of the disk 75, bent inwardly approximately at right angles to the plane of the disk, forms a contact arm 79 lying within a recess 80 in the edge of the switch member 14 and bearin with spring pressure against the walls of t ie base 11 and adapted in the closed position of the switch to enga e the contact stud 26. This serves to estab ish a ground connection for the contact stud 26, for the arm 79 of disk 7 5 engaged therewith has electrical connection with the casing by the spring tongues 77 of the disk bearing on the flange 78 of the front plate which is provided with a suitable ground connection not shown.

In the center of the base 11 is an upstandby four evenly spaced contact buttons 82, 83, 84 and embedded in the insulating com sition of the base, the contact button 82 being connected by wirc'87 with contact stud 82 and contact button 84 being connected with a binding post 86, while the other two contact buttons 83 and 85 form binding posts.

Loosely mounted on the post 81 is a disk 88 of insulating material having a ratchet connection with the switch member 14 so as to move therewith only in the movement of the latter toward its on position. Such ratchet engagement is afforded by a series of radially disposed ratchet teeth 89 formed on the bottom of the switch member 14 around an opening capable of receiving the end of the post 81 and ratchet teeth 90 cut from a metal disk 91 which is secured to the top of the insulating disk 88 by having arms 92 with their ends passing therethrough and bent over on the other side. The ratchet disk 88 has a ratchet-contact enga ement with the buttons 82-85 by means 0 a pair of oppositely placed spring contact members 93 which are curved to follow the path of rotation and are secured at their forward ends to the disk 88 by projections 94 passing through the disk and turned over on the other side thereof, and also by tangs 95 entering openings in the disk without passing entirely therethrough. Thus the s ring contact members 93 are carried by t e disk 88 from the disk 91 and its connection with the switch membflr vnected between tributer 117 driven by the successively 14. Each of the spring contact members 93 itself constitutes a spring tongue for bearing on the heads of the contact buttons, but further has a supplemental spring tongue 96 cut therefrom and bent downwardly to engage the head of the contact button in advance of the one engaged by the end of the contact member 93. The free ends of the spring contact members 93 and their supplemental spring tongues 96 by engaging the edges of the heads of the contact buttons constitute a ratchet connection permitting the disk 88 to turn only in the one direction so that with each succeeding operation of the switch from the off? position to the on position the disk 88 is given a one quarter turn. As each contact member 93 contacts with two adjacent contact buttons each contact button will be connected thereby, first with the contact button on one side thereof, and then with the contact button on the other side thereof to reverse the polarity of the current flow through a circuit conthe binding posts 87.

In connecting up the switch the binding post of contact stud 22 is connected by a wire 97 with one terminal of a generator armature 98 whose other terminal is grounded at 99, and the binding post of contact stud 23 is connected by a wire 100 with one terminal of a storage battery 101 whose other terminal is grounded at 102. This last mentioned binding post of contact stud 23 is also connected with a wire 103 forming one line Wire of an electric lighting circuit including electric lamps 104, the other line wire thereof being grounded at 105. The shunt field winding 106 of the generator has one end connected with the same armature terminal as wire 97 and the other end connected by a wire 107 with contact stud 26 so that when the spring contact arm 79 engages this contact stud the generator circuit is complete from the grounded armature terminal thereof through the armature and its other terminal through the shunt field winding 106, wire 107, engaged contacts 26 and 79 and disk 75 to the grounded front plate 10 indicated on the diagram by the ground connection 108. The binding post 85 is connected by a wire 109 with the primary winding 110 of an induction coil whose movable armature 111 serves to make and break the circuit therethrough by cooperating with a fixed contact point 112 which is connected by a wire 113 with binding post 83. The binding, post 86 which is connected with contact stud 84 has a wire connecting it with the ground at 120. The secondary winding 114'of the induction coil has one terminal grounded at 115 and the other terminal connected by a wire 116 with the arm of a disengine to contact with "stationary contact points 118 connected with the respective grounded spark plugs 119 of the various cylinders of the engine.

In that position of the switch in which its parts are shown in the diagram, besides the generator circuit being complete through the engagement of contacts 26 and 79 the working circuit through the electric lamps or other electroreceptive devices and the battery charging circuit are 'also complete through the engagement of the contacts 29 with the contact studs 22 and, 23 respectively. Starting with the grounded armature terminal of the generator the storage battery charging circuit includes the armature 98, wire 97, contacts 22 and 29, connecting wire 30, contacts 29 and 23, wire 100, storage battery 101 to ground 102. The working circuit is the same up to contacts 23 and thence through wire 103, lamps or other receptive devices 104, and ground connection 105. The ignition circuit beginning with the grounded armature terminal includes said armature, wire 97, contact stud 22, wire 87, contact button 82, spring contact 93, cont-act button 85, wire 109, primary winding 110 of induction coil, armature 111, stationary cont-act 112, wire 113, contact button 83, spring contact 93, contact button 84, binding post 86, and ground 120. The circuit for the induced current of the secondary windingof the induction coil may be traced from the grounded terminal 115 through the secondary winding 114, wire 116, distributer arm 117, one of the contacts 118 and its spark plug 119 to the ground. 7 At times when the generator is not operating these various circuits may be supplied with current from the. storage battery through the switch connections, as described, and the battery current thus directed through the generator will cause it' to operate as a motor for starting the gas engine.

When the switch is thrown to the ofi position the generator and ignition circuits are interrupted since the generator shunt field circuit is broken by the disengagement of contacts '26 and 79 renderingthe generator ineffective for supplying current for any purpose, and the storage battery is disconnected from all circuits'except the work circuit so that it is ineffective for causing ignition. Thus with the switch locked in its off position and the key removed the storage battery may-be used for lighting, but neither the storage battery nor the generator may be caused to produce ignition for starting the engine, and the automobile is efiectively locked against theft. \Vith the next closing of the switch to its on position the various circuits will be restored as before, with the exception that the spring contact members 93 will be advanced a quarter turn so as to connect cont-act buttons 82 and 83 on the one hand and contact buttons 84 and 85 on the other, and thus reverse the direction of flow of current through the primary circuit of the induction coil. ith this new position of the switch the prima circuit of the induction coil may be trace from the grounded terminal 99 of the generator armature through said armature 98, wire 97, contact stud 22, wire 87, contact button 82, spring contact member 3, contact button 83, wire 113, stationary contact 112, armature 111, primary winding 110, wire 109, contact button 85, spring contact member 93, contact button 84, binding post 86 to ground 120. With each succeeding closing of the switch a reversal will be made in the direction of flow of current through the primary circuit of the induction coil from that which prevailed during the preceding connection, and thus any tendency to produce pitting of contact points during one connection willbe neutralized or oflset by the opposite tendency due to the change in direction 0 flow of current through the primary circuit of the induction coil during the succeeding CODDGCUOIL he contact for a greater length of time than won] the case if no provision were made for the reversal of current by the pole changing feature. This pole changing feature is not confined in use to this particular switch mechanism, but is applicable ing an oscillating or reciprocating motion which may be converted by ratchet means to a rotary motion for the pole changing member.

The specificdetails of construction, while not necessary to the invention in its broader meritorious .as making the urable and highly eflicient for the purpose while' being inexpensive-to manufacture.

It is obvious that instead of the switch member being con ned to movement it may be arranged to have a rotary movement with an operative position at each quarter turn and with suitable provision for non-interference between the main switch and the shunt field circuit switch, and in such case there is no necessity tor a ratchet connection between the insulating disk 88 and the switch member 14, but it may be fixed thereon.

What I claim as new and desire to secure by Letters Patent is:

1. A starting switch for a battery chargenerator driven by a gas engine, comcasing having a pair of which is connected with one end of the shunt field winding of the generator and the ungrounded enerator armature terminal and the ot ier of which is connected with the ungrounde storage battery terminal, a switch member adapted to engage and disengage theswitch points will thereforebe kept free from pitting and will remain in operative condigion be I the an oscillating closing operation of the switch to contacts to establish connection between the end of the 7 of which is connected with one shunt field winding of the generator and the un ounded generator armature terminal an the other of which is connected with battery terminal, as a switch member adapted to engage and dis-- enga the switch contacts to establish connection between the generator and the storage battery, a third switch contact within the casing connected with the other end of the shunt field winding of the generator an I insulated contact arm carried by the switch' member and having, a groun connection and adapted to engage the third switch contact of the casing when the switch member is in position to complete the circuit between enerator and't e storage battery,'four insu ated contact buttons in the bottom of the casing symmetrically arranged about the axis of movement of the switch member, 11 two opposite contact buttons having connection with the ground and the generator armature connected switch contact respectively, an induction coil ignition mocha-I nism having a make and break device in its 1 primary circuit and with said primary circuit terminals connected tively wit contact buttons,

the other pair of opposite and a le changer havin connection m the switch member and a apted to connec 1 the contact buttons in pairs and cha the order of connection with each su 'ng alternate the direction of flow of current thro h the primary circuit of the induction co with the succeeding operations of the swi 3. A starting switch for a battery charging generator .driven by a gas engine, comprising a switch casing having a pair 0 switch contacts one of which is conn with one end of the'shunt field winding or the generator and the uiigioun ed generator armature terminal and the other of which is connected with the ungrounded storage battery terminal, a switch member adap to engage and disengage the switch contacts to establish connection between the genera third switch connected witl the shunt field Wind!!! 0,

ator and the storage battery,

contact within the casing the other end of the generator, an insulated contact arm carried by the switch member and having a ground connection and adapted to engage the third switch contact of the casing when the switch member is in position to complete the circuit between the generator and the storage battery, a grounded ignition circuit connected with one of the pair of switch contacts, and means operated by the movements of the switch member for changing the polarity of the ignition circuit.

4. In an electrical system for internal combustion engines, the combination with a source of current, a starting motor, and an interrupter, of means for simultaneously controlling the circuit of said motor and reversing the connections of said interrupter y to said source of current.

In; an electrical system for internai combustion engines, the combination with a source of current, a starting motor, and an interrupter, of a switching mechanism for simultaneously controlling the circuits of said motor and said interrupter, said mech amsm operating to' reverse the connections of said interrupter to said source of current at each actuationto complete saidcir cuits. v

6. In an electrical system for internal combustion engines,

source of current, a starting motor, and an ignition circuit comprising an interrupter,

the combination with a of a switching mechanism for simultaneously controlling the electrical connections of said motor and said circuit to said source and for reversing the connections of said mechanism for controlling the electrical con-=j nections of said motor to said source and comprising a ratchet mechanism for revers ing the connections of said interrupter upon the closing of said motor circuit.

In an electrical system for internal combustion engines, the combination with a source of current, a starting motor, and an ignition interrupter, of a unitary switching mechanism for simultaneously connecting said source to said motor and to said interrupter said mechanism comprisin an operating handle and a reversing switch, and a ratchet mechanism for operatively connecting said handle to said. reversing switch. i

In testimony whereof, I aflix my signa= ture, in presence of two witnesses.

STEPHEN F. BRIGGS.

Witnesses M E. Smm, 

